At the outset, we formulate three critical questions that need to be addressed to bridge the gap between engineering boiling research and physics research on single-vapor bubble dynamics at the nanoscale: (i) How do bubble growth and transition dynamics at the nanoscale differ from those at the macroscale? (ii) What is the connection between the governing dynamics at the two scales? (iii) How can vapor bubble seeds improve the engineering limits of boiling heat transfer. Both from the perspective of thermodynamics [1]} and that of fluid mechanics [2]}, the governing dynamics at the 100 nm scale are expected be different owing to confinement effects, leading to different bifurcation mechanisms of the boiling structure [3]}, [4]}, [5]}. Owing to the lack of sufficient experimental studies and theoretical understanding of nanoscale boiling, we first need to address the first question and clarify boiling at the single-nanobubble limit, before the scale gap between nanoscale and macroscale boiling can be bridged.
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